Compensable joint



J. E. CARTER GOIPENSABLE JOINT Filud Jan. 21, 1935 June 4, 1940.

2 Sheets-Sheet 1 1 y 4 4 3 m H fflEe O 71 W n 3 A n n H h m m 2 n 3 2; m a a a) 3 June 4, 1940.

J. E. CARTER COIPENSABLE JOINT Filed Jan. 21, 1955 2 Sheets-Sheet 2 INVENTOR. 070722 6. barzi r ATTORNEY.

' I v m I Claims,

The invention relates particularly, although not exclusively, to joints oi the inner vertical edges of adjacent concrete slabs of concrete highways, streets, and the like.

It is well known that the co-efiicient of expansion of concrete highways, streets, sidewalks, and the like, is relatively great which results in considerable damage being efiected to said concrete.

unless efficient means are provided to permit the concrete to expand and contract without exerting strain on relatively great lengths oi said concrete. For this reason, concrete highways, streets and sidewalks usually comprise a plurality of concrete slabs whose inner edges are spaced apart a sufllcient distance to permit the slabs to expand fully without contacting the inner edges thereof. Either permitting the inner edges of the concrete slabs to contact each other, or filling the spaces between'said slabs with any substance incapable of being readily compressed results in the concrete buckling and cracking when the temperature becomes sufilciently high to cause the concrete to expand beyond'the limit 01' the co-efllcient of flexibility of said concrete.

Heretofore, considerable difliculty and inconvenience has been experienced by builders of concrete highways, streets, sidewalks, and the like, in providing joints of concrete slabs which will compensate for the expansion and contraction of said slabs and prevent damage to said slabs during said expansion and contraction. Frequently the spaces between the adjacent slabs are filled with plastic fillers such as asphalt, or like substance, and after a period 01' time has elapsed, dirt, water, and other foreign substances, as a result of natural elements and movement of vehicles over the highway, enter the spaces between the slabs and adjacent the filler especially after the filler has been compressed by expansion of the slabs, and the slabs contract when the temperature is lowered, or after the filler has cracked or otherwise disintegrated. In other in-'- stances the spaces between the slabs are filled with metal fillers which are adapted to be loosened, and permit entrance of dirt, water and other foreign substances, between the slabs after the fillers have been damaged or have been rendered inefllcient as a result of the expansion and contraction or the slabs.

It is well known that when the spaces between the slabs of a concrete highway, street or sidewalk are filled with sand, dirt, and the like, suchv materials cannot be compressed, when the concrete slabs expand, whereby expansion oi. the slabs causes the slabs to warp or bend, crack,

PATENT OFFICE and otherwise be damaged because concrete is inflexible and unless the slabs are free to expand without any or a great deal of resistance the slabs 'will crack.

Therefore, the objects of the invention are to provide a simple, efllcient and practical joint of the inner edges of the concrete slabs forming a concrete highway, street, sidewalk, or the like; to provide a resilient member in the space between said slabs, said resilient member being adapted to be compressed when said slabs expand and being adapted to expand when said slabs contract whereby the space between said slabs is at all times sealed against entrance of dirt, sand, water, or other foreign substances; to provide means to retain said resilient member substantially in a fixed and predetermined position with respect to said slabs, said means being disconnected from said slabs whereby movement of said slabs,'caused by expansion and contraction, is unlikely to impart movement to said means or effect damage to said slabs; and to provide a foot fixed to the bed of said highway, a pair of spaced apart forms or retainers adapted to be connected with the inner edges of said slabs, said forms or retainers being connected with said foot in a manner adapted to permit said forms or retainersto slide horizontally when horizontal movement is imparted to said inner edges of said slabs by expansion and contraction, whereby the inner edges of said slabs are adapted to move horizontally without substantial interference'or restriction by the joint or any portion thereof.

The invention consists in the combination of the elements, arrangement of the parts and in the details of the construction, as hereinafter claimed.

In the drawings:

Fig. 1 is a plan view 01 a ribbon, or roadway, partly broken away; 1

Fig. 2 is a section taken on a line corresponding to 2-4 in Fig. 1, with parts broken away;

Fig. 3 is a section taken on a line corresponding to 3-3 in Fig. 2, with the concrete removed; and with parts broken away;

Fig. 4 is a section taken on a line corresponding to 4-4 in Fig. 2,'with the concrete removed, and with parts broken away;

Fig. 5 is a section taken on a line corresponding to 5-5111 Fig. 2, with the concrete removed, and with parts broken away;

Fig. 6 is a section taken on a line corresponding t 6-6 in Fig. 8 and with parts broken away;

Fig. 7 is a side elevational view of a block, with parts broken away;

Fig. 8 is a perspective view of a sleeve:

Fig. 9 is a section taken on a line corresponding to 9-9 in Fig. 2, with the concrete removed, and showing parts broken away; and

Fig. 10 is a perspective view of a form retainer, with parts broken away.

In the preferred construction of the invention, comprising the compensable joint I, I provide the vertical spaced apart angular form retainers 2 and 3 each of which comprises the upper and lower horizontal legs 4 and 5 having their inner ends integrally formed with the vertical body 6. In the upper legs 4 are a plurality of spaced apart slots 1 having received therethrough the vertical stay-rods 8 whose lower ends 9 are embedded in the road bed i0, which may be formed from suitable material, such as asphalt, sand, gravel, concrete, or the like. The road bed Ill is supported by the ground over which the intended ribbon or highway ll, sidewalk, or the like, is constructed.

The ribbon II is formed from a plurality of horizontal slabs l2 having their upper surfaces I3 in horizontal alignment and having their adjacent inner vertical edges l4 and i5 spaced apart, thereby forming the spaces or cuts l2 therebetween which extend transversely of the ribbon ii and in parallel relation with each other.

The upper legs 4, of the form retainers 2 and 3, are embedded in the inner vertical edges i4 and i5 of the adjacent slabs I2 and spaced from the upper surfaces l3 of the slabs. The upper legs 4 are embedded in the slabs l2 so that the vertical bodies 5 are fixed to the outer surface of the inner edges i4 and I5 of the slabs.

The lower horizontal legs 5, of the form retainers 2 and 3, are supported by the horizontal body I6, of the angular foot or support H. Integrally formed with the outer edges l8 and I 5, of the support i1, are the downwardly extending legs 20 and 2i which are embedded in the road bed iii.

In the lower horizontal legs 5, of the form retainers 2 and 3, are the slots 22, whose walls extend outwardly from the bodies 6. Slidably received in the slots 22 are the rivets 23 whose heads 24 slidably contact the upper surfaces of the legs 5. Each of the rivets 23 have the stem 25 received in the hole 26 in the body iii, of the support IT. The rivet 23 has the shoulder 2'! received in contact with the upper surface of the body iii of the support H, and the enlarged lower end 28 of the rivet 23 is received in contact with the lower surface of the body l6 of the support [1, whereby the rivet is retained in fixed position with respect to the support I! of either or both of the form retainers 2 and 3. The legs 5 are adapted to slide horizontally in contact with the upper surface of the body iii of the support I! when movement, longitudinally of the ribbon II, is imparted to the form retainers.

Positioned over the slots 22 and rivets 23 are the covers 29 having their inner and outer ends 30 and 3i fixed, as by the rivets 32, to the body 6 and legs 5 of the form retainers 2 and 3, whereby the slots 22 are kept free from concrete, dirt, and other foreign substances which may interfere with free horizontal slidable movement of the lower legs 5, of the form retainers.

During construction of the ribbon H, and after the stay-rods 8 are fixed in the road bed I and green concrete is poured onto the road bed and in contact with the form retainers 2 and 3, which forms the slabs I 2, the green concrete is prevented by the covers 23 from entering the slots 22 or contacting the rivets 23.

Received in the spaces or cuts i2/, and between the inner vertical edges l4 and I5, of the slabs i 2, and in contact with and between the vertical bodies of the form retainers 2 and 3, are the resilient strips or blocks 33 which may be formed from rubber or other suitable material. The upper edge 34, of each of the blocks 33, is substantially in horizontal alignment with the upper surfaces l3 of the slabs i2. The lower edge 35, of the block 33, is in contact with the upper surface of the body l5, of the support l1, and supported by the supports.

Fixed to the inner surfaces of the bodies 5, of the form retainers 2 and 3, are the nipples 35 and 31 having the internal threads 38 therein to which are threaded the external threads 39 on the outer surfaces of the inner ends of the sleeves 40 and 4i which extend horizontally. Slidably received in the sleeves 40 and 4| and extending through the holes 42 and 43 in thebodies 5, of the form retainers 2 and 3, is the floating or slidable bar 44 which is received'through the hole 45 in the resilient block 33, whereby the block 33 is retained in predetermined position with respect to the slabs l2.

When the slabs l2 expand, as a result of variations of the temperature of said ribbon II, the inner edges l4 and I5 of the slabs l2 advance toward each other, and when the slabs contract the edges I4 and-l5 retreat from each other.

As previously mentioned, the bar 44 is free to move horizontally within the sleeves 40 and 4|, inward and outward movement of the edges i4 and I 5, of the slabs I2, caused by expansion and contraction of the slabs, does not effect movement of the bar 44 which retains its predetermined position for the purpose of maintaining the resilient block 33 in stationary and predetermined position with respect to the inner edges l4 and I5, of the slabs l2, and the form retainers 2 and 3. When the slabs l2 expand, as their temperature increases, and the inner edges thereof advance toward each other, the resilient block 33 is compressed. When the slabs l2 contract, as a result of their temperature decreasing, and the inner edges thereof retreat from I each other, the resilient block expands and remains in close and sealing contact with the bodies 5, of the form retainers 2 and 3, and also in'sealing contact with the inner edges of the slabs above the horizontal legs 4 of the form retainers 2 and 3.

When constructing the ribbon H, the vertical legs 20 and 2|, of the supports H, are embedded in the road bed [0 after which the form retainers 2 and 3 are properly positioned in spaced apart relation with each other, depending upon the temperature at the time of installation. The supports I! and the retainers 2 and 3 have been previously assembled with the rivets 23 connecting the legs 5, of the form retainers 2 and 3, with the body iii of the supports i1, and the covers 25 are fixed to the form retainers 2 and 3. Then the form retainers 2 and 3 are fixed in an adjusted position as by inserting the vertical stay rods 8 through the slots I in the horizontal legs 4 and the lower ends of the stay-rods are driven into the road bed ill. Then the resilient blocks 33 are inserted between the bodies 6 of the form retainers 2 and 3, preferably under slight compression. Then the bar 44' is inserted through the nipples 36 and 31, respectively, fixed to the are screwed into the nipples 36 and 31.

bodies 8, of the form retainers 2 and 3, and through the holes 45 in the resilient blocks 33 and positioned so that the distance which the ends 46 and 41 of the bar 44 extend outwardly from the bodies 6, of the retainers 2 and 3, is approximately the same. Then the sleeves l and 4| Then the slabs l2 are formed by pouring suitable material, such as concrete, into the forms previously constructed to form the outer edges of the ribbon Ii until the upper surface of the slabs is in horizontal alignment with the upper edge of the ad- Jacent resilient blocks 33. While the concrete sets or hardens the retainers 2 and 3 automatically become fixed to the edges l4 and I5, of the slabs I2, and the upper edges of the slabs contact the upper end of the block 33.

An advantage of the invention is that the resilient block 33 is adapted to seal the space l2 between the slabs l2, whereby entrance of sand, dust, water, or other foreign substances, in said space is prevented. Also, the resilient block 33 is retained in a predetermined and substantially fixed position with respect to the retainers 2 and 3, and the edges l4 and I5 of the slabs l2 as by the bar 44, which is disconnected from the slabs whereby the slabs are adapted to move horizontally by expansion and contraction without damaging the joint I of the slabs i2.

Another advantage of the invention is that the retainers 2 and 3 are slidably connected with the foot or supports I'I, whereby the retainers 2 and 3 are adapted to slide horizontally and yet be supported by the supports I! when the edges I4 and I5 of the slabs move horizontally inwardly and outwardly as a result of expansion and contraction of the slabs, and the connections of the supports II with the slabs I2-remains substantially the same and without damage to the slabs irrespective of ordinary movements of the slabs.

Still another advantage of the invention is that the upper edge of the block 33 is formed from resilient material, such as rubber, and is unlikely to impart excessive vibration to a vehicle which travels over the highway H because the resilient block 33 is adapted to be compressed in horizontal alignment with the upper surfaces of the slabs i2 by contact of the vehicle wheels. Moreover, when the resilient block 33 is utilized in the joint I between the slabs of a sidewalk the foot of a person, who walks over the sidewalk, will compress the contacted upper edge of the block substantially in horizontal alignment with the upper surfaces of the slabs l2.

While I believe that the form of the invention illustrated in the drawings and referred to in the above description, as the preferred embodiment, is efllcient and practicable, yet realizing that the conditions concurrent with the adoption of the device will necessarily vary, I desire to emphasize the fact that changes in the details may be resorted to, when required, without sacrificing any of the advantages of the invention as defined in the claims.

Various changes may be made in the general form and arrangement of mechanical parts described without departing from the invention. Henceldonotlimitmyselftotheprecisedetails of the materials or the size and shape thereof as set forth, but consider myself at liberty to make such changes and alterations as fairly fall within the spirit and scope of the appended and final claims.

What I claim as new and desire to secure by Letters Patent is:

1. The combination with an expansible and contractible concrete street positioned on a road bed and comprising a plurality of horizontal slabs having spaced apart vertical inner edges and having their upper surfaces substantially in horizontal alignment, a vertical form retainer being fixed to each of said edges and having a space therebetween, a resilient block positioned between said retainers, and sealing said space, means movably mounted in the edges of said slabs and extending through said block to retain said block substantially in predetermined position irrespective of movements of said slabs caused by expansion and contraction, a foot member fixed in said road bed,

means slidably connecting the lower edges of said retainers with said foot member, said last mentioned means adapted to prevent vertical movements of said retainers and permit horizontal movements thereof.

2. The combination with an expansible and contractible concrete street positioned on a road bed and comprising a plurality of horizontal slabs having spaced apart inner edges, a form retainer being fixed to each of said edges and having a space therebetween, a block positioned between said retainers, means movably mounted in the edges of said slabs and extending through said block to retain said block substantially in predetermined position, a foot member fixed in said road bed, means slidably connecting the lower edges of said retainers with said foot member, said last mentioned means adapted to prevent vertical movements of said retainers and permit horizontal movements thereof.

3. The combination with an expansible and contractible street comprising a plurality of horizontal slabs having spaced apart vertical inner edges and having their upper surfaces substantially in horizontal alignment, a vertical form retainer being fixed to each of said. edges and having a space therebetween,. a resilient block positioned between said retainers, and sealingsaid space, means movably mounted in the edges of said slabs and extending through said block to retain said block substantially in predetermined position irrespective of movements of said slabs caused by expansion and contraction.

4. The combination with adjacent vertical edges of horizontal concrete slabs having their upper surfaces substantially in horizontal alignment, of vertical retainers being spaced apart from each other and being fixed to said edges, means intermediate said retainers, and means to retain said means in predetermined position with respect to said retainers, the upper edges of said retainers being lower than the upper surfaces of said slabs and the upper edge of said block being substantially in horizontal alignment with 

